Moored Wellhead Effluent Capture and Concrete Application Apparatus

ABSTRACT

An improved moored wellhead effluent capture apparatus consists of multiple nested pressure resisting enclosures with open bottoms and increasing outside dimensions, interconnected with structure and resting on a common plane, the seabed, for encasing wellheads. Each surface of said pressure resisting enclosure is disposed with aligned holes of similar diameter for the purpose of connecting pipes used for a multitude of functions. The apparatus deployment over a blown out wellhead can be accomplished by lowering the apparatus over the drill pipe, allowing the pipe to pass through an open hatch in the top while descending to enclose the wellhead on the seabed for removal of the effluent through a conduit located on an auxiliary pipe flange. The removal of fluid from inside the void between the pressure resisting enclosures results in a net force from the hydrostatic pressure pushing the apparatus into the seabed, effectively mooring the structure around the wellhead. The said moored wellhead effluent capture apparatus aids blown out, existing, and new wellheads by providing a multitude of means for the installation of structural reinforcement, the placement of concrete and aggregate for encasement of the well pipe or wellhead, both above and below the seabed, and the excavation of for subsea foundations.

CROSS-REFERENCE TO RELATED APPLICATIONS Search Reference:

5,213,444 May 25, 1993 Henning 5,050,680 Sep. 24, 1991 Diehl, et al.4,382,716 May 10, 1983 Miller 4,358,218 Nov. 9, 1982 Graham 4,324,505Apr. 13, 1982 Hammett 4,318,442 Mar. 9, 1982 Lunde, et al. 3,965,687Jun. 29, 1976 Shaw 3,719,048 Mar. 6, 1973 Arne, et al.

FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

None

SEQUENCE LISTING OR TABLES

None

BACKGROUND OF THE INVENTION Field Of Invention

The present invention relates to the containment or recovery of liquidsand gases erupting from a blown out oil well with emphasis on thecontainment method and apparatus used to secure a blowing wellhead orfissure in the sea floor and the conveyance of the hydrocarbons to thesea surface.

Insurmountable environmental damages, loss of natural resources and theloss of life are historic results of underwater oil well blowouts. Theenvironmental impacts of such disastrous spills are noted through theloss of tourism and the use of fisheries, to the devastation of speciesand their habitat.

The companies financially responsible for the cleanup of the spillsencounter enormous expenditures as a result of the attemptedenvironmental cleanup and the litigations that represent the affectedpeople and industries. The suspension of drilling operations and thetightening of regulations for drilling further exacerbates the financesof the responsible companies. Furthermore, the loss of the hydrocarbonswhich are not recovered for production further impacts the financialstability of the company due to lost revenue. As a result, a oncethriving company which once provided financial security to manycommunities may become jeopardized, or worse, insolvent.

Therefore, it is the primary object of this invention to provide a newand improved effluent entrapment means for subsea blowouts. Thisinvention addresses the issue of avoidable catastrophic environmentaldisasters as a result of wellhead blowouts by the capture of thehydrocarbons for use in post blowout conditions and improvement of thecurrent drilling process technology by the addition of redundant systemsand the offering of new features in non-blown out subsea installments.

An inverted open bottomed pressure vessel, the capture vessel, ofdimensions to encompass subsea equipment, has a hole cut in the top toaccept a vertical cylinder, mechanically attached to the center, withample diameter through which the original well pipe can easilymanipulate. Similarly, an outer dome, the vacuum vessel, of largerradius, has a hole cut to accept mechanical attachment through which thecenterline vertical cylinder penetrates. Above the vacuum vessel, acylinder is attached at an angle to the side of the center, verticalcylinder. The upper end of the center cylinder has a head with a hatchwhich can be remotely closed. The upper end to the auxiliary cylinder istopped with an auxiliary elbow, arranged such that acceptance of anotherpipe from a rig is possible, and a remotely controlled valve. Alternatetopping arrangements to the auxiliary pipe are an alignment cone forremote aligning, threaded fitting, or pipe swaging apparatus.

The base of each vessel terminates on the same horizontal plane, and, asrequired, typical radial and concentric bulkheads are fit between thetwo dome vessels. Each bulkhead is fitted with air and fluid holes sothat the flow of air, fluids, or concrete is not impeded. Extendingbelow the plane and mechanically attached to each dome are cylinderswith vertical axis and of corresponding radius. At the dome to cylinderjoints, or as close to as practicable, a compression bar is placed onthe outside surfaces of cylinders, parallel to the horizontal plane.

In addition to typical wellhead equipment, the following are added:gauges, cameras, lights, a hydraulic or pneumatic system, rams andactuators, necessary controls and wireless circuitry or tethers, avacuum pump and required valves and equipment.

In use of the preferred embodiments, a tug, anchor handling offshoresupply vessel, or a rig crane, with the apparatus hatch open andrequired tethers connected, lower the apparatus onto the existing pipeand into the water, using it as a guide to the wellhead. New pipe can beattached to the auxiliary pipe flange for a tandem pipeattachment/decent operation. A light and camera inspect the damaged pipefor obstructing defects during the decent. Once the above apparatus isin place above the blowing wellhead the decent is stopped and a remoterobot removes the pipe from the damaged blowout preventer. Once removed,the apparatus is lowered around the blowout preventer and the pipe ispulled through the hatch. At this time, a vacuum is pulled on the spacebetween the outer and inner vessels by evacuating water. This forcepulls the cylindrical sections of the apparatus into the seabed to adepth of the compression bar at the dome to cylinder joints. With thevacuum remaining and verified by gauges, the hatch can be closed byremote control or robot sending the hydrocarbons into the auxiliarycylinder. If the auxiliary cylinder is not plumbed with pipe, the valvemay be required to be open during the closing of the hatch to allow theeffluent to escape.

BACKGROUND OF THE INVENTION Objects and Advantages

Accordingly, besides the objects and advantages of the Method andApparatus as described in my above patent, several objects andadvantages of the present invention are:

-   -   a. The addition of the evacuation vessel to the original        effluent containment arrangement, which has anchors at small        tether angles to the horizontal plane, is that larger vertical        forces from the fluid flow of the hydrocarbon can be overcome.    -   b. The integration of the hatch allows the exact placement of        the apparatus assuming the original pipe remains tethered to the        wellhead.    -   c. The pulling of the apparatus into the seabed effectively        seals the wellhead allowing for 100% operable condition. Without        containment vessel seal to the seabed a fraction of the        hydrocarbons would escape.    -   d. Integration of existing or new pipes with several options as        to how the connection may be made: threaded, or swage connection        with a conical guidance system.    -   e. Remotely controlled hatch and vacuum devices allow for        long-term operations without the need for a standby robot.    -   f. The addition of concrete into the space between the two        vessels through an additional valve allows for long-term        wellhead encasement solutions.    -   g. Cylindrical sections and compression rings add structural        integrity, aid in the ease of deployment, and allow for ample        safety factors for deep water wellheads.    -   h. Cameras and lights allow for troubleshooting, and aid in        deployment.    -   i. The addition of adding structurally reinforced concrete in        excavated cavities to encase subsea wellhead equipment or        provide adequate foundations for such structures is aided by a        lifting and securing device, excavation equipment, and concrete        placement valves for use in new installations or expansions.    -   j. An additional evacuation valve connecting an auxiliary        containment vessel to the capture vessel allows for the capture        of effluent.

SUMMARY

In accordance with the present invention the Moored Wellhead EffluentCapture and Concrete Application Apparatus, is comprised of a capturevessel, an evacuation vessel, vertical chimney with dogged hatch,auxiliary chimney with shutoff valve, alignment cone and pipereceptacle, concrete fill nozzles with shutoff valves to the evacuationand capture vessels, hydraulic or pneumatic equipment and bulkheads asrequired, cameras, lights and support equipment as necessary, tether asnecessary, instrumentation and required controls, and vacuum nozzle andsupport equipment. The successful construction and deployment of theapparatus allows for more successful capture of effluent and securing ofthe wellhead, and offers safer wellhead operation and encasement processof the drill pipe below the seabed.

DRAWINGS Figures

FIG. 1 shows the elevation view of the apparatus with open hatch beforethe cutting of the original pipe and after the pulling of seawater fromthe evacuation vessel to lower the apparatus into the seabed in both theblown out and non-blown out configurations.

FIG. 2 shows the elevation view of the apparatus after the cutting ofthe original pipe, with closed hatch and after the installation of thenew pipe in the blown out configuration.

FIG. 3 shows the plan view of the apparatus with closed hatch after theinstallation of the new pipe.

FIG. 4 shows the plan view of the apparatus with open hatch in thenon-blowout installation.

FIG. 5 shows the elevation view of the auxiliary configuration of theapparatus with closed hatch pipe seal, lifting and securing device,excavation equipment, and effluent valve after the pulling of seawaterfrom the evacuation vessel to lower the apparatus into the seabed innon-blown out configuration.

DRAWINGS Reference Numerals

-   11 capture vessel dome-   12 capture vessel cylinder-   13 capture vessel compression bar-   14 evacuation vessel dome-   15 evacuation vessel cylinder-   16 evacuation vessel compression bar-   17 evacuation vessel bracket-   18 radial bulkhead-   19 concentric bulkhead-   20 chimney cylinder-   21 chimney head-   22 hinged, dogged hatch-   23 auxiliary chimney cylinder-   24 auxiliary chimney shutoff valve-   25 auxiliary chimney guide cone-   26 auxiliary chimney receiving flange-   27 evacuation and fill valve-   28 control room watertight bulkheads-   29 mechanical equipment-   30 capture vessel concrete fill valve-   31 evacuation vessel concrete fill valve-   32 camera, light, and mounting bracket assembly-   33 pressure sensor-   34 original pipe-   35 new pipe-   36 drilled hole-   37 concrete-   38 subsea equipment-   39 ballast-   40 seabed-   41 hatch to pipe seal-   42 lift and securing device-   43 effluent valve-   44 excavation equipment

DETAILED DESCRIPTION Preferred Embodiment—FIGS. 1 Through 3

The preferred embodiment of the present invention, Moored WellheadEffluent Capture and Concrete Application Apparatus, is shown in FIG. 1,elevation, before the original pipe 34 is removed from the subseaequipment 38 in order to allow for the effluent to be diverted from theoriginal pipe 34 to new pipe 35, as shown in FIGS. 2 and 3, elevationand plan, respectively. The capture vessel dome 11 is mechanicallyconnected to capture vessel cylinder 12 forming an impervious connectionresilient to high pressures. The capture vessel compression bar 13 restson seabed 40 and is mechanically connected to capture vessel cylinder 12or capture vessel dome 11 to assist in structural integrity. Theevacuation vessel dome 14 and evacuation vessel cylinder 15 aremechanically connected forming an impervious connection resilient tohigh pressures. To assist in structural integrity and the resting of theApparatus on the seabed 40, evacuation vessel compression bar 16 andevacuation vessel bracket 17 are mechanically connected to evacuationvessel dome 14 or evacuation vessel cylinder 15. To further assist indealing with large hydrostatic and dynamic forces, radial bulkhead 18and concentric bulkhead 19 are mechanically connected to capture vesseldome 11 and evacuation vessel dome 14. The chimney cylinder 20 ismechanically connected by an impervious joint at the top of capturevessel dome 11 and evacuation vessel dome 14 where holes are cut incapture vessel dome 11 and evacuation vessel dome 14 for the passage ofchimney cylinder 20. Resting atop chimney cylinder 20 is the chimneyhead 21 mechanically connected by an impervious joint. Above the chimneyhead 21 is the hinged, dogged hatch 22 through which the original pipe34 passes when open and is mechanically connected with an imperviousjoint to chimney head 21. Mechanically attached with an imperviousconnection in series to chimney cylinder 20 are auxiliary chimneycylinder 23, auxiliary chimney shutoff valve 24, auxiliary chimney guidecone 25 and auxiliary chimney receiving flange 26 for the redirection ofeffluent to a new pipe 35 once the original pipe 34 is disconnected tosubsea equipment 38 and hinged, dogged hatch 22 is closed. Mechanicallyattached with an impervious connection to evacuation vessel dome 14 isevacuation and fill valve 27 for use to evacuate fluids from evacuationvessel dome 14 by mechanical equipment 29 in the control room watertightbulkheads 28 mechanically connected with an impervious connection to theApparatus. Mechanically attached with an impervious connection tocapture vessel dome 11 is capture vessel concrete fill valve 30, and theconnection to evacuation vessel dome 14 is made with the evacuationvessel concrete fill valve 31. The camera, light, and mounting bracketassembly 32 is rigidly connected to the Apparatus at strategiclocations. Similarly, pressure sensors 33 are placed at strategiclocations for troubleshooting. Additionally, ballast 39 is placed on theApparatus to assist in the capture vessel cylinder 12 and evacuationvessel cylinder 15 in making a good seal with the seabed 40 upon impactwith said seabed 40.

Operation—FIGS. 1 Through 3

The operation of the preferred embodiment of the present invention,Moored Wellhead Effluent Capture and Concrete Application Apparatus, isshown in FIG. 1, elevation before the original pipe 34 is removed fromthe subsea equipment 38. The Apparatus deployment is from a workboat oroilrig crane via tether to contain blown out subsea equipment 38. Thehinged, dogged hatch 22 is opened to allow the original pipe 34 is to beguided through the open bottom and to pass through the hinged, doggedhatch 22 while lowering the Apparatus. The Apparatus is then loweredinto the water with capture vessel concrete fill valve 30 and evacuationvessel concrete fill valve 31 open to allow air to escape from the openbottom Apparatus. Once submerged, capture vessel concrete fill valve 30and evacuation vessel concrete fill valve 31 are now closed inpreparation of the encasement of the subsea equipment 38. A new pipe 35may or may not be attached during the descent of the Apparatus andauxiliary chimney shutoff valve 24 should be open. The Apparatus thendescends to the seabed 40 while being guided by the original pipe 34where the subsea equipment 38 becomes encased by capture vessel cylinder12 and the effluent becomes guided through chimney cylinder 20, chimneyhead 21, and then hinged, dogged hatch 22. Once the Apparatus is on theseabed 40 the evacuation and fill valve 27 evacuates water from the voidspace between capture vessel cylinder 12 and evacuation vessel cylinder15 causing the hydrostatic pressure within the void to become less thanthe hydrostatic pressure head of the water above the evacuation vesseldome 14 resulting a net vertical force in the downward direction pushingthe capture vessel cylinder 12 and evacuation vessel cylinder 15 intothe seabed 40 until capture vessel compression bar 13 and evacuationvessel compression bar 16 are on seabed 40 and the subsea equipment 38is encased inside of capture vessel dome 11. At this time the robot canremove the original pipe 34 from subsea equipment 38, causing theeffluent to become more volatile, and the robot assisted or automaticclosing of hinged, dogged hatch 22 can take place as shown in FIGS. 2and 3, elevation and plan, respectively. Once the hinged, dogged hatch22 is closed the effluent is then diverted to the auxiliary chimneycylinder 23 and to the new pipe 35.

Operation of Alternate Embodiments—FIGS. 1, 4, and 5

An alternate use of the invention is to deploy the Apparatus as in thepreferred embodiment above before a blowout occurs from subsea equipment38 or a drilled hole 36. Typically, the use would be such as shown inFIGS. 1 and 4, elevation and plan. In the event of such an occurrence,the procedure in the preferred embodiment could then be continued as inthe preferred embodiment to capture any flowing hydrocarbons from subseaequipment 38 or drilled hole 36.

In addition to the auxiliary function of encasing the subsea equipment38 in the event of a post-installation blowout, concrete 37 could bepumped into drilled hole 36 through capture vessel concrete fill valve30, encasing new pipe 35. In the event of failed subsea equipment 38,concrete 37 could be pumped to fill the capture vessel dome 11, sealingoff the subsea equipment 38 leak. The auxiliary configuration of FIG. 5offers the means for deploying structural reinforcement by using liftand securing device 42. Furthermore, the lift and securing device 42aids in the use of subsea excavation equipment 44.

Furthermore, the addition of a hatch to pipe seal 41, and an effluentvalve 43 connected via a conduit to a an auxiliary containment vessel,the auxiliary apparatus configuration of FIG. 5, elevation, couldcapture smaller amounts of effluent while still offering the protectionof the auxiliary chimney assembly for use in connecting an additionalcapture pipe.

The addition of the apparatus to existing and new wells makes thetypical drilling operations safer and less prone to spills due toredundant systems, the ability to effectively deploy structurallyreinforced encasement concrete and effluent capture technology.

ADVANTAGES

From the description above, a number of advantages of the MooredWellhead Effluent Capture and Concrete Application Apparatus are:

-   -   a. The capture and containment of effluent as a result of a        blown out wellhead or subsea equipment becomes more certain and        reliable in the event of unstable seismic or pressure        circumstances when the containment vessel, and the attached        piping, are adequately moored to the seabed.    -   b. The Apparatus allows for the production of hydrocarbons to        resume, once the system is fully installed and tested over a        blowout, until redundant blowout systems can be installed or        another well is drilled.    -   c. Concrete can be pumped into the void space between the two        domes through the concrete valve effectively creating a more        permanent structure.    -   d. In the event of the desired long term abandonment of the        wellhead, concrete can be pumped through another valve into the        capture dome sealing off the entire wellhead.    -   e. In new wells concrete can be pumped into the drilled hole        encasing the well pipe reducing the affects of blowouts and the        likelihood of oil spills.    -   f. Hole structural reinforcement can be deployed from the        lifting and securing device as well as excavation equipment. As        a result, larger reinforced foundations can be constructed for        subsea and wellhead installations as well as offering additional        means for excavation and access below these foundations.    -   g. Reversible vacuum pump and valve allow for the increase or        decrease of pressure inside the void space under the evacuation        dome resulting in a lift or descent of the apparatus.    -   h. By installing the Apparatus before the well goes into service        auxiliary environmental protection and safety is offered by        providing the ability to divert effluent emanating from blown        out subsea equipment into the secondary manifold by        disconnecting the original piping and closing the vertical        manifold hatch.    -   i. In the auxiliary installation the addition of a pipe hatch        seal to drill pipe, and an effluent valve attached to        containment vessel via a conduit could serve as an additional        measure against environmental containment.    -   j. With the installation of the auxiliary configuration, using a        multitude of nested vessels, the auxiliary stack pipe connecting        the capture vessel could serve as a secondary product conduit in        tandem with the main central product conduit, thus serving as a        separation pressure vessel.

CONCLUSION, RAMIFICATIONS, AND SCOPE

If offshore drilling is to advance in depth, volume, and is becomingmore accepted in seismically and environmentally sensitive regions ofthe world, reliability of the equipment and the processes in which theindustry relies upon will have to become less prone to catastrophicresults due to the failure of any key component.

1. An improved moored wellhead effluent capture apparatus includingrigid means for collecting at least hydrocarbons leaking from anunderwater source in which the improvement comprises rigid means for thereduction of pressure between a larger vacuum vessel surrounding andcontiguous to an effluent capture vessel so that the hydrostaticpressure above said vacuum vessel slidably forces the effluent captureapparatus into the seabed to a predetermined depth, thereby surroundingsubsea equipment and existing pipe located on the seabed with saidmoored wellhead effluent capture apparatus comprising: a plurality ofnested pressure vessels with open lower ends and closed upper ends, saidclosed upper ends each being provided with at least one opening therein,disposed above and surrounding the underwater leak, said open lower endsof the pressure vessels disposed with the seabed; and a verticalpressure vessel fayed to and projected from said opening in said upperend of the effluent capture vessel, fayed to said opening in said upperend of said vacuum vessel, projecting vertically from said vacuumvessel, fayed to a concave pressure vessel with open lower end and aclosed upper end, said closed upper end being provided with at least oneopening therein; and a dogged articulate hatch fayed to said opening ofsaid upper end of said concave pressure vessel, the open dogged hatchallowing means for aligning the disposed vertical conduit providingmeans for extracting the hydrocarbons from the subsea equipment; and aninclined vertical pressure vessel fayed to and projected from saidopening in said upper end of the effluent capture vessel, fayed to andcontiguous to said opening in the said vacuum vessel, inclined from saidvacuum vessel, fayed to a shutoff valve disposed to and fayed to a pipeconnector, disposed to and fayed to an angled vertical pressure vessel,disposed to and fayed to a conical cylinder with open lower end and aopen upper end, said upper end having the larger diameter therein; and aslidable conduit edge disposed to said conical cylinder fayed with saidpipe connector, the conduit to provide means to extract said leakinghydrocarbons contained within said effluent capture vessel cavity; and amultitude of structural members contiguous to and fayed to said effluentcapture vessel and said vacuum vessel; and providing means for removingor adding fluid from the void between said effluent capture vessel andsaid vacuum vessel.
 2. The apparatus of claim 1, further including aplurality of means for providing vertical cylinders fayed to said openlower ends of said concentric pressure vessels, further including aplurality of perpendicular flanges fayed to said vertical cylinders,disposed in proximity to the open lower ends of said concentric pressurevessels, disposed in a single horizontal plane and contiguous with theseabed, providing means for stopping the descent of the verticalcylinders into said seabed.
 3. The apparatus of claim 1, furtherincluding a plurality of means for removing or adding fluid or slurry tothe effluent capture apparatus; whereby, providing means for theencasement of the subsea equipment or pipe.
 4. The apparatus of claim 1,further including a plurality of means for providing lighted cameras;whereby, providing means for remotely monitoring the activity andcondition of the subsea installation.
 5. The apparatus of claim 1,further including a plurality of means for the automatic remote openingand closing of valves and hatches.
 6. The apparatus of claim 1, furtherincluding a plurality of means for providing a mechanical space, whereinthe mechanical and control equipment is to occupy said mechanical space,whereby, providing means for encasing the mechanical and electricalequipment therein.
 7. The apparatus of claim 1, further including amultitude of means for detection of pressure in the effluent captureapparatus.
 8. The apparatus of claim 1, further including a plurality ofmeans for providing and receiving communication with said mechanicalcontrol equipment located at an unspecified distance from the apparatus.9. The apparatus of claim 1, further including a plurality of means forreceiving power to the mechanical and control equipment located at anunspecified distance from the apparatus.
 10. The apparatus of claim 1,further including a plurality of means for receiving fluids to themechanical and control equipment located at an unspecified distance fromthe apparatus.
 11. The apparatus of claim 1, further including means forthe placement of concrete around subsea equipment below the seabed. 12.The apparatus of claim 1, further including means for the placement ofaggregate around subsea equipment below the seabed.
 13. The apparatus ofclaim 1, further including means for auxiliary containment of installedsubsea installations.
 14. The apparatus of claim 1, further includingmeans for the placement of the subsea reinforcement structure.
 15. Theapparatus of claim 1, further including means for the placement of thewell reinforcement structure plug.
 16. The apparatus of claim 1, furtherincluding means for the discharge of effluent through a valve disposedin the capture vessel providing conveyance of effluent to a vessel. 17.The apparatus of claim 1, further including a plurality of means for theseal sandwiching the hatch to the pipe.
 18. The apparatus of claim 1,further including a plurality of means for the lifting and securing ofthe subsea structural reinforcement and excavation equipment.
 19. Theapparatus of claim 1, further including a plurality of means for theexcavation of seabed material.
 20. The apparatus of claim 1, furtherincluding a plurality of means for the simultaneous discharge of amultitude of hydrocarbon products through the valves, inclined andvertical pressure vessels. SEQUENCE LISTING: None